♪♪ -The first 3 months of life are truly special.

Babies must learn the most basic of skills to thrive and, for some animals, to even survive.

♪♪ In Kenya, a newborn elephant calf, Safina, is learning how to keep up with her fast-moving herd.

♪♪ In Sri Lanka, 1-week-old Jazir has to quickly learn the ropes of a primate society that's enmeshed with the world of people.

At the edge of the Arctic, 5-week-old fox cubs must learn to hunt in the limited window before the harshness of winter sets in.

♪♪ And in Uganda, an 8-month-old mountain gorilla has to learn to cope with a fast-changing environment.

♪♪ Like all babies, these young animals will have a first year filled with joy, love, and play.

♪♪ But there will also be challenges... [ Elephant grunts ] [ Macaques chitter ] [ Sea otter barks ] ...sometimes on a daily basis.

[ Hyena growls ] [ Macaques squeak ] [ Thunder rumbling ] [ Roars ] -I'm quite nervous because lions don't like hyenas.

♪♪ -To tell the stories of these magical months, four renowned wildlife cinematographers will follow the lives of our baby animals as they grow and develop.

♪♪ -This is pretty unreal, actually.

I get treated with a little baby boy.

He's just a few hours old.

-[ Lowered voice ] This is the stuff that makes elephants so exciting.

It's just the way we are.

-This is the story of what it takes to survive in the wild.

This is their first year on Earth.

-It's almost like seeing your kid ride their bike for the first time.

♪♪ ♪♪ -The first 3 months is when our animal babies have to rapidly get to grips with their new family and the challenges of the environment that surrounds them.

♪♪ It's the end of Northern Kenya's dry season, and a family of African elephants gathers at a critical time to protect a vulnerable new arrival.

Scientists call her Safina.

She is just a few hours old.

[ Elephant rumbling ] 3 feet tall, 200 pounds in weight, she is the biggest baby born on land.

Safina's mother, Cyclone, with the single tusk, is the herd matriarch.

[ Elephant rumbles ] Safina was in her womb for almost 2 years.

From the minute she is born, she is in a race for survival.

She must muster the strength to stand and suckle, and within hours, she must start to walk to keep up with the herd as they search for food and water.

♪♪ Bob Poole has spent decades filming elephants, which has given him a unique affinity to, and understanding of, them.

-We've been searching all morning long for this matriarch, who's just had a infant.

This calf, we're gonna follow all year long and watch it through its first year of life.

♪♪ -In this family, there's another baby 2 weeks older.

She has already developed the coordination to keep up with the herd for hours at a time.

But the herd won't stop for a newborn Safina for long.

Her survival relies on keeping up from her first day.

[ Elephant rumbling ] If she falls behind or is separated from her mother, she could be a target for predators.

[ Elephant rumbling ] The herd walks up to 9 miles a day looking for food.

Safina may cover over 2,000 miles in her first year.

[ Engine turns off ] -There's the baby right there.

[ Whispers ] That's so awesome.

My god.

♪♪ Aah!

"I can't go!

I can't go!"

♪♪ [ Chuckling ] [ Whimsical tune plays ] Still stuck in the mud.

♪♪ It's gonna have such a hard time getting up and out of there.

♪♪ [ Cyclone grunts ] ♪♪ ♪♪ -One of the most fundamental survival skills Safina must learn is how to use her trunk.

She won't be able to drink, feed, or communicate without it.

♪♪ 150,000 bundles of muscle fibers allow it to stretch, contract, and twist through 360 degrees with precision.

An adult can lift nearly 800 pounds, so her mother can tear a branch from a tree or pluck a single blade of grass.

♪♪ -Baby like this has to learn how to use all that, and it takes time.

So you see them all the time, you know, pulling on things and mimicking their -- their mothers, actually.

♪♪ -It will take Safina a year to learn how to gather food and water, but she can already use her trunk to touch and smell, which is how she forms bonds.

And in such social animals, survival depends on forming these bonds quickly.

There are three mothers in the herd, and their young.

All the females will help protect the young, but males do not.

Safina has a 1.5-ton adolescent brother.

[ Suspenseful music plays ] He doesn't know how to behave around vulnerable babies.

♪♪ And at just 4 days old, she hasn't learned that he could be dangerous.

♪♪ ♪♪ [ Suspenseful music climbs ] [ Elephant rumbles ] [ Suspenseful chord strikes ] ♪♪ ♪♪ 16 times her weight, a kick back in irritation could severely injure her.

[ Elephant roars ] The females surround Safina with a wall of muscle and tusk.

[ Elephant rumbling ] It's important that Cyclone keeps within touching distance in these first crucial weeks.

♪♪ [ Jaunty tune plays ] Safina is now 12 days old.

Bob is tracking her family with the help of GPS data from conservationists Save the Elephants -- pioneers in elephant collaring and tracking.

♪♪ -So this is the mountain range I'm looking at right here.

She's been right up on top of the ridgeline there, and good news is, she's coming our way now.

[ Elephant growling ] -But calls coming from the herd indicate the family is agitated, and they are getting extremely close to Bob's vehicle.

[ Elephant growling ] -Do you hear that?

-Suddenly, another herd emerges from the scrub.

They're calling to Safina's family.

-There's gonna be a fantastic greeting.

This is -- these are obviously related elephants.

They don't do this unless they're, like, family, okay?

So this -- this is an amazing moment right now.

I'm telling you, you don't get this every day.

-It turns out that the matriarch of the other herd is Cyclone's sister, Monsoon.

-Here they come.

Now watch what happens when they get together here.

[ Elephants rumbling ] ♪♪ They're bonding.

You see, this -- this is like -- It's like giving each other a hug after they've been away for a long time.

♪♪ [ Elephants rumbling ] -This could be the very first time Safina has met her aunt and cousins.

Now she has the chance to memorize their smells and calls, so she can recognize them as family and friends in the future.

♪♪ -They don't do this with every elephant they come in contact with.

This is because they know each other.

Like, you know, when we've been separated from our family, and we're so happy to be back together again, and that's exactly what's going on right now.

♪♪ [ Elephant trumpets ] -By using her trunk to touch and smell, Safina is beginning to create the bonds that she will remember for a lifetime.

[ Birds chirping ] ♪♪ [ Elephant rumbling ] ♪♪ Parental protection is essential for surviving the first year, but some babies also have to work out complex family structures.

♪♪ ♪♪ 6 miles from the border between Kenya and Tanzania, one of Africa's most successful predators is in the middle of a baby boom.

♪♪ [ Cubs squeaking ] ♪♪ A dozen cubs have been born in the past 3 months to this spotted hyena clan.

♪♪ They all live with their mothers at the den, and, again, males here do not play any part in parenting.

♪♪ They are often misrepresented as scavengers, but this clan hunts for most of their food.

[ Cubs squeaking, nursing ] Hyenas are dedicated mothers, and they nurse their cubs for twice as long as their archrivals -- lions.

[ Hyena yawning ] They live in a female-led hierarchy with a queen in charge.

And scientists have recently discovered they are highly socially intelligent.

♪♪ They call this mother Soup.

She is second-in-command.

[ Cub squeaking ] She has twin daughters -- Bisque and Chowder.

They are 12 weeks old and the highest-ranking cubs.

♪♪ Only half of hyena cubs survive their first year, but if the twins work as a team, they could dramatically increase their chance of survival, and that teamwork first develops around now.

[ Cubs squeaking ] ♪♪ Wildlife cameraman Vianet Djenguet was born in the Republic of Congo, one of the 44 African countries in the hyena's home range.

He has come to the Maasai Mara to find out if the sisters have what it takes to thrive in this competitive environment.

-In this hierarchy, there's gonna be rules, and those rules, you have to get them right from this age.

This is just the start of the process.

-12 weeks old is the age when they begin to learn how to enforce the rank they inherit from their mother.

Working as a team, they soon make their presence known.

[ Cubs squeaking ] -Oh!

[ Laughs ] It's really great to see them with the other cubs, throwing their weight around.

♪♪ -But to survive unscathed, they must learn the rank of all 60 hyenas in the clan.

-It's really complex to understand how their social structure works.

[ Barks, growls ] -The sisters learn by watching their mother's body language.

When she rises and goes into a tall stance with a bristled tail, it signifies dominance.

The signals for submission include a bobbing head, flattened ears, and backing off.

This is the etiquette that holds the clan together.

So the sisters have to get it right every time they encounter another hyena.

-Thing is to keep that position in the rank, you have to fight for it, pretty much.

[ Birds chirping ] -This youngster is 6 months old, twice their age, but his mother has a lower rank than theirs, so he is subordinate.

The twins must both give him a clear dominant signal of their status.

[ Cubs squeaking ] [ Low growling ] [ Snarls ] With their mother's support, the older cub submits.

They are sending out the right signals.

[ Low growling ] Day by day, the sisters' confidence is growing at the den, but they know little of the dangers lurking outside it.

♪♪ Lions patrol the same territory.

They are the biggest rival for food and greatest threat to their lives.

More hyenas are killed by lions than anything else, and they kill cubs to eliminate competition.

♪♪ [ Squeaking ] ♪♪ -I just have to remind myself that half of those cubs won't make it.

-This is the most dangerous year of their lives.

♪♪ The twins are now 13 weeks old and are learning to combine forces to dominate the den, but they must also learn they can't use aggression against every hyena in their clan.

[ Hyena whooping ] This 2-year-old male will put them to the test.

He's the queen's son, so he outranks the cubs and their mother.

[ Suspenseful music plays ] -Bisque and Chowder must get this right.

They must.

♪♪ They'll need to show respect.

♪♪ If they get this wrong, they could get badly beaten.

-Hyenas have been known to kill others in the clan to maintain rank.

He's spotted the two sisters, and because of his superior status, their mother cannot defend them if they get it wrong.

♪♪ [ Tender tune plays ] With their ears back and heads bobbing, they're making all the right signs of submission.

From reading his body language, they calculate he is one of the few hyenas that ranks higher than them.

♪♪ -Bisque and Chowder are learning really fast.

One minute, they pick on the other cubs because they learn they can; and the next minute, turns out they learn that he's higher than them, and they were submissive and sweet.

♪♪ -From watching their mother, Bisque and Chowder have mastered an important step in negotiating interclan politics.

♪♪ But as they grow up, they have to move outside the den and into unknown enemy territory, where there are lions.

♪♪ ♪♪ Most wild babies have to find a way to survive threats from predators, but some face the additional challenges of learning to live alongside humans.

♪♪ The Pacific Coast of North America is home to around 3,000 southern sea otters.

♪♪ Wildlife cameraman Colin Stafford-Johnson has filmed otters in the wild all around the world, but has come to Monterey to see the challenges for a pup trying to survive so close to people.

-Right now, it's winter, and when storms hit this coastline, there is simply no place to hide.

Out here, creatures really are at the mercy of these deep cold seas, but, perhaps surprisingly, this is the time of year when some southern sea otters give birth and raise their young.

[ Suspenseful music plays ] -Most new mothers raise their pups in the kelp forest along the wild coast.

♪♪ But this sea otter is different.

She is bringing up her pup inside the man-made marina at Monterey, a busy fishing port on the Californian coast which lands more than 10,000 tons of fish a year.

♪♪ Here, they can avoid winter storms, but they are exposed to risks, including boat strike and pollution.

-Really see how these otters are very much growing up in a human-dominated world.

-Sea otters were once hunted to the edge of extinction for their fur.

They are now protected, but still live with the impact of humans.

This pup has to learn to identify risks as he grows to make it through.

[ Motor whirring ] -You know, I've been racking my brains, trying to think about a name for this young pup.

I think I'm gonna call him Limpet 'cause he's constantly stuck to his mum.

-Limpet is 6 weeks old.

Until now, he has either floated on the surface or rested on his mother's belly.

But the time is coming for him to take his first critical step towards independence, because sea otter mothers leave their pups at around 6 months old.

-My real mission is to try and capture an important moment, a vital moment, in a young otter's life, and that's when it learns to dive for the very first time.

♪♪ He isn't able to dive beneath the surface, as yet.

Its got too much air in its fur.

-Otters have the densest fur of any mammal.

The tip of Limpet's tail has more strands of hair than an entire human head.

♪♪ Air trapped in the fur next to Limpet's skin keeps him warm and buoyant.

-And until they can dispel that air, it's like a little life jacket and it means that they can't actually dive down and follow Mum.

[ Otter bleats ] -If he can't dive, he can't avoid boats or learn to feed himself.

Limpet's fluffy coat will soon molt, but he also has to practice diving to build up essential muscle strength.

This marina is just Limpet's nursery, so his mother tows him out to practice in the ocean.

But conditions out here are more dangerous.

-The pup's going to learn the sea's got a little bit more inherent movement and a few more currents and things out here, so it's gonna get that bit of exposure.

[ Seals barking ] [ Suspenseful music plays ] -His mother spends up to 10 hours a day hunting, leaving Limpet alone to practice.

-The youngster's going down.

He's trying.

♪♪ I mean, I guess when he sticks his head under, he's able to watch and see what his mum is doing, and he's desperate to follow her, but he's just got a little bit too much buoyancy yet.

♪♪ ♪♪ -Limpet is now 6.5 weeks old, but still hasn't built up the stamina to practice for long.

[ Bright tune plays ] ♪♪ Next morning, practice begins again... ♪♪ ...and Michelle Staedler of Monterey Bay Aquarium joins Colin.

She has been studying the otters here for the past 30 years.

♪♪ -It seems like the pup is quite impatient to get under the water.

-Yes.

He's also not physically able to dive that way.

His muscles, his bones... Much like toddlers, when they start to walk, all of a sudden, they can do it, and the same thing will happen with him, is, all of a sudden, he'll be able to dive a little deeper.

There's also a lung capacity issue, so he can't hold his breath as long and he will be able to go down for a short time and, eventually, over time, they build up the ability to hold more oxygen in their lungs.

-While he can't keep up with his mother underwater, he is at risk.

[ Suspenseful music plays ] Only half of sea otter pups make it through their first year.

-We'd had a lot of sharks in this area, so if the pup were on the surface by itself, the shark may come up and grab it.

-Great white sharks bite on objects they spot on the surface to work out if it's food they want to eat.

Sea otters are not part of their diet, but the otters are too small to survive the wounds.

So, inadvertently, 50% of otter fatalities are from shark bite.

♪♪ [ Tranquil tune plays ] ♪♪ Limpet is now 7 weeks old.

His muscles and coordination are improving every day, but he still hasn't completed his first dive.

♪♪ -It's gone!

He's gone underwater.

Oh!

Come up again.

That is a moment.

It's a real moment.

It's almost, like, you know, seeing your kid ride a bike for the first time, and that is going to change everything.

That moment means that, from now on, he's gonna learn to follow Mum underwater.

♪♪ -But Limpet's next challenge is even harder.

♪♪ He needs to learn how to find food in a crowded and dangerous man-made environment.

[ Bird whistling ] ♪♪ ♪♪ The most successful animal families include those that are quick to take advantage of any opportunity that helps them and their babies thrive.

♪♪ On the tropical island of Sri Lanka, the ruins of an abandoned capital are now home to a new line of royalty -- toque macaques, found nowhere else on Earth.

[ Chittering ] Scientists are interested in their complex social interactions and believe that rank directly affects the babies' chances of survival in their first year.

♪♪ And, last night, the alpha female of this troop gave birth to a son.

♪♪ Sue Gibson is a wildlife camerawoman who has a passion for primates.

She has the extraordinary privilege of being in Sri Lanka to witness his first days on Earth.

-A few hours ago, one of the troop's given birth, which is amazing and... [ Grunts ] an excellent opportunity to try and get some shots of a newborn macaque.

I think I can see it.

[ Chittering ] This is pretty unreal, actually.

I get treated with a little baby boy.

He's just a few hours old.

-Scientists have named him Jazir.

He weighs just under a pound, but could treble that if he makes it through his first year.

-Jazir's mum, being the alpha female, means that Jazir might one day go off and form a troop of his own and be alpha male of that troop.

-But Jazir has been born just before the dry season, the worst time for macaques... ♪♪ ...when the vegetation they eat dries up.

♪♪ To make it through the next 3 months, Jazir must learn how to exert his authority and use the advantage he's been born with.

♪♪ -Don't look them in the eyes.

It's a threat in monkeys.

-Sue is working with Dr. Wolfgang Dittus of the Smithsonian Institute, head of the longest running primate study in the world, almost 50 years.

It's revealed the impact rank has on an infant's chances.

-It gives them a sort of priority of access to whatever contested resources there are, like figs, like fruit, like water and resting places, and all those things translate into their body condition and their ability to survive and, ultimately, to reproduce.

You know, if you're always privileged in getting the best food, the best water, sitting out of the Sun in the shade, being the first one up on the tree when there's a predator coming -- That sort of translates into survivorship.

-So there's no guarantee that Jazir will survive his first year?

-No.

There's no guarantee.

Only about 60% of babies that are born survive to the first birthday.

-Wow.

-So there's a pretty high rate of mortality in the first year.

-And only 10% of males go on to make it to adulthood.

The toque macaque population is now endangered, as it loses habitat across Sri Lanka to human development.

Jazir's forest sanctuary is a fraction of the size it once was.

The ancient ruins of Polonnaruwa are a small protected haven in the middle of a busy modern city.

[ Horn honking ] ♪♪ [ Chittering ] ♪♪ Living so close to people can have its upsides, but temple macaques have more chances to find food than monkeys living in the wild.

♪♪ but where there are people, there are dogs.

[ Various animals calling ] [ Suspenseful music plays ] Feral dogs hunt monkeys, especially babies, like Jazir.

♪♪ -These dogs look like they mean business.

They're looking straight at our troop.

They've got a certain swagger about them, that's for sure.

♪♪ He's definitely -- he's definitely interested because he's salivating.

-Low-ranking macaques at the edge of the troop act like sentries.

They are the first to see the threat.

[ Dog growling ] -So I hope Jazir and his mum are somewhere safe.

[ Dogs barking ] -Jazir's mother can always get up a tree first because top rank means the other monkeys have to wait.

♪♪ -[ Exhales deeply ] Phew.

That was a little bit of a thumping heart moment.

-Jazir's mother has protected him from the dogs by keeping him close, but to succeed in the first 3 months, he has to gain the confidence to explore.

[ Tranquil tune plays ] Jazir must learn to compete with his peers for limited resources on his own... ♪♪ ...and it all begins by letting go of his mother.

-[Grunts] -This is a little bit of a -- They're right here.

Your lucky day.

The first steps away from Mom.

-That's the first time we've seen that.

♪♪ So Jazir looks like he's trying to... -Explore the place.

-...explore a little bit, yeah.

But always going back to Mum after... -Yep.

-...a bit of time.

♪♪ -At just 9 days old, Jazir begins to interact.

He has developed the confidence to join in with the other baby macaques.

But if he is to live up to his high-pressure pedigree, Jazir must find the skills and build up his strength and assert his dominance.

♪♪ [ Wind gusts ] [ Music fades ] ♪♪ Every baby is precious to its mother, but some babies are precious to us all because they are so rare.

In Uganda, a tiny miracle is hidden in the last fragment of a once giant forest kingdom called Bwindi, the Impenetrable Forest... ♪♪ ...a baby mountain gorilla, Nyakabara.

♪♪ Her name means "marked" because she was born with a white bracelet of fur never seen before.

♪♪ Nyakabara is one of perhaps only 50 mountain gorilla babies in the world.

She is 8 weeks old and weighs around 5 pounds.

She shares 98% of her DNA with human babies, and, like them, is utterly dependent on her mother.

[ Gorilla rumbling ] ♪♪ Within days, she should develop an interest in her family group of 12... [ Branch snaps ] ...and the forest that will dramatically affect her chances of survival.

♪♪ The only other group of mountain gorillas is in the Virunga Mountains on the border with Congo and Rwanda, but they have been separated for 5,000 years.

♪♪ Unlike the Virunga gorillas, the Bwindi apes feed high in trees, even though some weigh more than 400 pounds.

[ Birds chirping ] Nyakabara's family will climb up over 80 feet to get to seasonal fruit.

It's fraught with danger.

♪♪ Their previous silverback fell to his death.

Another was struck by lightning as he slept in a tree.

♪♪ A third of babies don't survive their first years.

Falls are a factor.

♪♪ Vianet has filmed orphaned mountain gorillas before, but this will be the first time he has encountered such a rare family in the wild.

♪♪ Researchers from the Max Planck Institute are helping him.

They have spent 20 years unlocking the secrets of these arboreal great apes.

Vianet will only be allowed 4 hours a day with them once he finds them.

-Stop.

Oh!

Oh, oh, oh, oh, oh.

Gosh.

[ Gorilla vocalizes ] [ Whispering ] I'm just about to go and film mountain gorillas, and they're my favorite one.

But, as a protocol, I have to wear a mask because one of the biggest fright to them is human eviction, especially that little baby I'm going to be following for a year.

-The gorillas are endangered, fewer than 500 in Bwindi, and habitat loss restricts their growth.

♪♪ Thousands of people farm right up to the forest's edge, one of the densest rural populations in Africa.

♪♪ Legislation has stopped the forest shrinking, but there is no longer any room for it to grow... ♪♪ ...limiting the gorillas' population.

♪♪ Infanticide is another risk infants face in their first year.

Nyakabara's father is a muscular young silverback, the same height as Vianet, but he is 2.5 times his weight.

His role is to prevent a takeover by another silverback who would kill babies to father his own.

-That is the boss.

He knows that, and no one can take that from him.

[ Beats chest ] [ Suspenseful music plays ] -In the first 6 months, Nyakabara's mother stays close to the silverback for protection.

She doesn't welcome attention from other gorillas.

-It's very hard trying to get a shot of the mother and the baby at this stage, [tearfully] and the mother, just trying to make sure that her baby doesn't get hurt.

They're so weak.

She just want to make sure she's protecting her little baby.

[ Beats chest ] ♪♪ -Not even the troop's other infant, Garode, is acceptable.

[ Whimsical tune plays ] ♪♪ -And what I'm hoping to see is those beautiful baby's eyes looking out and taking in her family and her surroundings.

♪♪ -The ancient forest sits on equatorial mountaintops at nearly 8,000 feet.

Unique microclimates support almost 400 plant species and the highest diversity of trees in East Africa.

The mostly vegetarian apes seek out around 100 different plants for food.

It takes around 2 to 3 years to learn them all.

Nyakabara is 8.5 weeks old and supporting her own head.

Her eyes are just focusing.

-This is the first time I've caught the little baby's eyes open, and she looks stunning.

She's got spark in her eye.

-She is on the verge of crawling, 5 months ahead of a human baby, but she is still months away from being able to climb for herself.

♪♪ Her mother can't hold on to her as she forages.

Nyakabara must cling to her fur.

♪♪ -I can actually see the mother and the baby on the tree.

♪♪ That's a long way for the baby to be.

I hope that she's fine there.

♪♪ ♪♪ [ Branch snaps ] [ Thud ] [tearfully] I can't believe that branch just snapped!

I just hope baby's still alive.

-They have fallen out of sight, down a steep slope.

-Just can't see them at all.

♪♪ -Vianet cannot get down there.

♪♪ [ Various animals calling ] The next day, Vianet has to track the family from the fall site.

Garode is on her mother's back, but there's no sign of Nyakabara.

A flash of white reveals both survived the fall.

-[tearfully] Hey, Jack, is the baby okay, and the mother?

-It looks okay.

Luckily, there's lots of vegetation, so, it was a soft landing.

-That's a big relief.

♪♪ ♪♪ -Nyakabara is now 9 weeks old and is reaching the stage when, like a human baby, she can recognize family beyond her mother.

♪♪ [ Screeches playfully ] [ Whimsical tune plays ] ♪♪ -This is the moment I've been waiting for.

-For the first time, Vianet sees Nyakabara show interest in the group's other infant, Garode.

Nyakabara is just starting to connect to her troop.

As curiosity and coordination grow, the biggest challenge Nyakabara faces is to adapt to life in the trees herself.

She will have to learn to climb in order to feed and stay safe in the forest.

♪♪ ♪♪ The fjords of Northwest Iceland.

In winter, the Sun barely rises and temperatures can plummet to below zero Fahrenheit, but it is home to the island's only native land mammal: the arctic fox.

[ Barking shrilly ] Half the size of a red fox, they are perfectly adapted to live in this hostile environment, with one of the warmest coats of any animal.

Its highly insulatory fur even covers the pads of its feet.

♪♪ In June, the Icelandic summer brings a spectacular contrast to winter, with 24-hour daylight.

This is the time arctic fox cubs emerge, but they will only have 3 months to fatten up before most of their food disappears and the harsh winter returns.

Only half of the cubs survive their first year.

Colin is highly experienced in filming in extremely remote locations.

He has come to the Hornstrandir peninsula to see what it takes to survive with such limited time to develop.

But first, he has to find the cubs.

Arctic foxes vary in color.

♪♪ This male will keep his dark coat throughout the year... ♪♪ ...while his mate turns the classic white in winter.

♪♪ Their cubs will stay hidden in a den under rocks for up to 5 weeks.

♪♪ -Lots of places to hide amongst the boulders, but it really does look like a typical arctic fox den site.

♪♪ -But there's no way of knowing exactly when they'll emerge.

♪♪ ♪♪ [ Barking in distance ] ♪♪ [ Barking in distance ] -That could well be Dad calling not too far away.

♪♪ [ Barking in distance ] That's a good sign.

♪♪ Oh.

Oh.

♪♪ That was a fox cub.

Little fluffy brown back movin' amongst the boulders.

So they're definitely here.

-The 5-week-old cub weighs around 1.5 pounds and is about the size of a kitten.

-Wow!

Look to be the very same color as the dad, dark brown, but tiny.

-At this size, they are still vulnerable to cold, despite their warm fur.

They will only emerge for about an hour at a time.

♪♪ -There's at least six or seven.

Oh, there's a little white one.

♪♪ That's the one I'm gonna have to follow, 'cause I can't tell any of the others apart.

[ Cubs barking ] I'm going to call him Fela.

In Icelandic, it means "to hide" or "hidden," something like that.

Been hiding from me for a while, so... What a wonderful little animal.

♪♪ -In some countries, Arctic foxes have up to 14 cubs in a litter.

But in Iceland, they have fewer, as there is so little food.

There won't be enough food for all of this litter of eight.

They will have to fight for it.

-There is intense sibling rivalry between them, and, although this just looks like play, and I guess that's what it is, it has a very important function.

The stronger you are, the feistier you are, the more chance you have of accessing the food that the parents deliver to the site, the better chance you have of growing up, and it looks like, so far, Fela looks boisterous, and that's a good sign.

-Because they have so little time to learn, the fox cubs are already born with the instinct to hunt.

Arctic foxes practice a very particular hunting technique.

♪♪ When they detect the tiniest movement of rodents under the snow, they pounce.

♪♪ [ Rodent squeaking ] ♪♪ The last patches of snow act as a trigger for the cubs' instincts.

♪♪ -I find it intriguing how they know just how to jump out to do that sort of arctic fox leap.

These things are just ingrained and inbuilt.

♪♪ -But Fela isn't pouncing.

♪♪ With seven siblings as rivals for limited food, he cannot afford to fall behind.

♪♪ The only way to get through the winter, when they could face a month between meals, is to lay down fat from now on.

[ Birds squawking ] Their parents catch breeding seabirds from nearby cliffs to feed them, but the birds will leave by the end of summer, and then, there will not be enough food to go around.

-Survival is not guaranteed in this part of the world.

The summers are very short, and a litter of a eight is going to need a lot of food, a lot of food deliveries, every day.

If they don't get them, they won't make it.

And the sad thing is, if they just miss out on a few meals, they get weak, and then they just lose out on that competition.

♪♪ -Life will always be a struggle for Fela.

Out here, only the toughest survive, but his ability to get to food first and bulk up in the race towards winter will ultimately determine if he makes it through his first year on Earth.

♪♪ ♪♪ -To order "Animal Babies: First Year on Earth" on DVD, visit ShopPBS or call 1-800-PLAY-PBS.

This program is also available on Amazon Prime Video.

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